In U.S. Pat. No. 3,760,844, issued Sept. 25, 1973, to Paul E. Olson et al., and assigned to the assignee of the present application, there is shown a circuit module for fluid distribution which module includes a fluid circuit plate that has formed in one or both of its opposite sides a plurality of polygonal chambers, each chamber being separated from an adjacent chamber by a thin wall or partition. Each end of each of these walls or partitions intersects and is formed integral with two or more other partitions. If this fluid circuit plate were made by casting a thermoplastic material in a mold, such a circuit plate, subsequent to removal from the mold, would creep or flow upon tightly clamping the circuit plate between an upper and a lower cover plate, at least one of which is constructed of a suitable metal, to form a circuit module.
Therefore, it is desirable that the fluid circuit plate be constructed of a more rigid material such as, for example, a thermoset plastic. When the fluid circuit plate is constructed of a thermoset plastic material, which is comparatively brittle, it has been found that, upon effecting severing of a selected single partition, which separates two adjacent chambers, by gripping the partition between the jaws of a suitable tool and thereafter twisting the tool to sever and remove the partition, the locations of the points of severance are not always exactly at the respective opposite ends of the selected partition as would be most desirable. Often a portion of one or more of the intersecting partitions is undesirably removed along with the selected partition, or an unwanted fracture or rupture occurs in one or more of these intersecting partitions. Should such a fracture or rupture occur in a partition separating two adjacent chambers, one of which constitutes a part of one passageway in the fluid circuit plate and the other a part of another passageway in this circuit plate, fluid under pressure flowing through either passageway would flow into the other if no fluid under pressure, or fluid at a lower pressure, were present in the other passageway. The resulting flow of fluid under pressure into this other passageway could cause an undesired operation of the logic control valve device to which this other passageway is connected. Consequently, this fluid circuit plate would be unfit for use and would have to be scrapped.
Accordingly, it is the general purpose of the present invention to provide a molded fluid circuit plate that comprises one or both sides thereof, or extending therethrough, a plurality of polygonal chambers, each separated from the chambers disposed thereabout by a plurality of thin, removable partitions. Each end of each of these partitions is integral with and severable from the corresponding one of one pair of a plurality of pairs of tapered strengthening posts or hubs, each of which has cast or formed integral therewith one end of several partitions each of which extends radially therefrom to a different one of the other posts or hubs.